Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Dunes Reveal Biodiversity Secrets

26.09.2014

Ancient, acidic and nutrient-depleted dunes in Western Australia are not an obvious place to answer a question that has vexed tropical biologists for decades.

But the Jurien Bay dunes proved to be the perfect site to unravel why plant diversity varies from place to place. Smithsonian Tropical Research Institute scientist Benjamin Turner and colleagues from the University of Western Australia published findings in the Sept. 26 edition of Science showing that environmental filtering—but not a host of other theories—determines local plant diversity in one of Earth’s biodiversity hotspots.

Turner and colleagues examined plant communities and soil development across a sequence of dunes ranging in age from a few decades to more than 2 million years. The dunes form as sand piles up along the coastline of Western Australia during periods of high sea level. The youngest dunes contain abundant soil nutrients but are home to relatively few plant species, whereas the oldest dunes have some of the most infertile soils in the world yet support many species of plants.

The differences in diversity of plants on the dunes are much better explained by environmental filtering—the exclusion of species from the regional flora that are poorly adapted to local conditions—than by alternative ideas related to competition for resources.

“Ecologists have long sought to understand what explains variation in species diversity among sites,” said Helene Muller-Landau, STRI staff scientist. “This elegant study shows that variation in plant species diversity among dunes of different ages, and thus different soils, is explained mainly by variation in the size of the pool of species adapted to these differing conditions.” Biogeographical and historical factors, like the total area in the region with similar conditions today and in the past, are primary, while factors such as competition for soil resources are much less important in explaining variation in species diversity.

“A number of mechanisms have been proposed to explain plant diversity along resource gradients, but they have not previously been tested simultaneously,” Turner said. “The Jurien Bay chronosequence allowed us to do this, and gave a clear result—that local plant diversity is explained primarily by environmental filtering from the regional flora.”

Jurien Bay is a rare example of a long-term chronosequence of soils in a species-rich ecosystem, making it an ideal location to test biodiversity theory.

“A challenge now is to examine this process along chronosequences in other species-rich ecosystems,” Turner said. “Unfortunately, there are as yet no long-term soil chronosequences with intact vegetation known under diverse lowland tropical forest.”

Turner expects the findings to spark a flurry of debate, but emphasizes that the research does not seek to explain the maintenance of biodiversity within individual communities, only how it varies among communities. Theories such as negative density dependence—that natural enemies maintain diversity in species-rich plant communities—are not challenged by this work, he said.

“It’s important to recognize that resource competition or other mechanisms can still maintain diversity,” Turner said. “But in terms of explaining why plant diversity varies from place to place, our results indicate that environmental filtering is the overriding explanation. ”

“I suspect that the answers will be different for different ecosystems in different places,” Muller-Landau said. “Here in Panama, and throughout the tropics, wet forests tend to have much higher species diversity than dry forests. This pattern is generally explained in terms of differences in ecological conditions, especially wet forests being more conducive to pathogen attack. But we’re not sure if this is the correct explanation. A study like this would help us to sort that out.”

Laliberté, E., Zemunik, G., Turner, B.L. (2014) Environmental filtering explains variation in plant diversity along resource gradients. Science 345 (6204; 26th September).

Beth King | Eurek Alert!
Further information:
http://newsdesk.si.edu/releases/dunes-reveal-biodiversity-secrets

More articles from Ecology, The Environment and Conservation:

nachricht International network connects experimental research in European waters
21.03.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

nachricht World Water Day 2017: It doesn’t Always Have to Be Drinking Water – Using Wastewater as a Resource
17.03.2017 | ISOE - Institut für sozial-ökologische Forschung

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

When Air is in Short Supply - Shedding light on plant stress reactions when oxygen runs short

23.03.2017 | Life Sciences

Researchers use light to remotely control curvature of plastics

23.03.2017 | Power and Electrical Engineering

Sea ice extent sinks to record lows at both poles

23.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>